In 1973, a registry and clinical study of patients with hereditary polyposis and colorectal cancer syndromes was initiated at the Johns Hopkins Hospital. In 1984, the Bowel Tumor Working Group was formed to study the biology of colorectal tumors and expanded the Registry functions. The Registry is maintained in a computerized DBase III database and now includes family histories and food frequency questionnaires of 547 expanded to include pancreatic cancer patients and serve to support investigations of the role of familial and environmental factors in the molecular genetic alterations in both pancreatic and colorectal carcinoma.